Wheel in which heterogeneous material is inserted

ABSTRACT

A wheel includes a main wheel having a stepped core part and a tire formed of a urethane material as an outer surface thereof, and an auxiliary wheel having a ring shape and provided on a circumferentially-central portion of an outer surface of the main wheel, on which the tire is provided, in an insertion manner. The main wheel is formed of a plastic material, and the auxiliary wheel is formed of a metallic material that is different from the material of the main wheel.

TECHNICAL FIELD

The present invention relates generally to a wheel in which a heterogeneous material is inserted and, more particularly, to a wheel having a structure in which a ring-shaped auxiliary wheel formed of a metallic material is inserted into and coupled to an outer circumferential surface of a main wheel formed of a plastic material.

BACKGROUND ART

Generally, representative equipment of leisure sports includes, for example, roller-skates, inline-skates, skateboards, essboards, kickboards, or the like, which are equipped with wheels formed of urethane to enjoy speed. Such leisure sporting equipment has a structure in which wheels are installed onto boots or boards to roll over the ground. Among the equipment having such a structure, a wheel of an inline skate will be exemplarily explained as follows. First, an inline skate has a structure in which a curved frame is provided on a lower portion of a boot, a plurality of coupling holes are formed in opposite sides of the frame, and a plurality of wheels are rotatably installed onto coupling axes inserted through the coupling holes. Such inline skates have been widely used by various age groups from children to the older adults, and they are especially popular as family leisure sporting equipment.

FIG. 1 is an exploded perspective view of the configuration of a conventional wheel for skates. As shown in FIG. 1, the wheel includes a hub section 10 and a urethane tire formed around the hub section 10. The hub section 10 has an inner ring portion 11, an outer rim portion 12, and a plurality of spokes 13 radially extending between the inner ring portion 11 and the outer rim portion 12. Two bearings 31 are installed in the inner ring portion 11 of the hub section 10 with a cylindrical spacer member 32 disposed therebetween. A fastening bolt 33 is inserted through both the bearings 31 and the spacer member 33 disposed therebetween, and is coupled to a base frame on opposite side thereof through coupling holes and fastened thereto with a nut 34, thereby forming an assembly. In such a wheel, the hub section 10, which has the inner ring portion 11, the outer rim portion 12, and the spokes 13, is formed of a light plastic material. Such a wheel, however, has limitations in increasing a rotational speed for skating. As an example, Korean Unexamined Patent Publication No. 10-2010-0137246 (published on Dec. 30, 2010) discloses such a wheel for skates.

DISCLOSURE Technical Problem

Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art, and an object of the present invention is to provide a wheel having a structure in which a ring-shaped auxiliary wheel formed of a metallic material is inserted into and coupled to an outer circumferential surface of a main wheel formed of a plastic material, thereby increasing a rotation speed of the wheel due to a local mass increase, which is caused by the insertion of the metallic material into the wheel, at the same volume by using the difference in specific gravity (density).

Another object of the present invention is to provide a wheel having a structure in which a ring-shaped auxiliary wheel formed of a metallic material is inserted into and coupled to an outer circumferential surface of a main wheel formed of a plastic material, thereby facilitating the variation of mass compared to a conventional structure formed of a single material through the difference in specific gravity (density) between the main wheel and the auxiliary wheel, thereby further improving driving performance.

Technical Solution

In order to accomplish the above objects, according to an aspect of the present invention, a wheel includes: a main wheel having a stepped core part and a tire formed of a urethane material as an outer surface thereof; and an auxiliary wheel having a ring shape and provided on a circumferentially-central portion of an outer surface of the main wheel, on which the tire is provided, in an insertion manner, wherein the main wheel is formed of a plastic material, and the auxiliary wheel is formed of a metallic material that is different from the material of the main wheel.

The auxiliary wheel and the main wheel may have a difference in specific gravity (density) and the metallic auxiliary wheel may be coupled to the outer surface of the main wheel so as to increase a rotation speed of the wheel due to a local mass increase at the same volume.

The main wheel may be provided with a protruded ring-type recess in which the auxiliary wheel is inserted into and coupled to along a circumferentially-central portion of an outer surface of the recess, wherein the auxiliary wheel protrudes farther than the protruded ring-type recess.

The main wheel may be configured such that the auxiliary wheel is integrally embedded in the circumferentially-central portion of the outer surface of the main wheel.

The auxiliary wheel having the ring shape may be formed of any one material selected from the group including steel, aluminum, tungsten, brass, titanium, and stainless steel.

The wheel in which the auxiliary wheel is disposed in the main wheel may be used for extreme sports, inline-skating, skateboarding, essboarding, kickboarding, or the like.

Advantageous Effects

According to the present invention, the wheel is configured such that the ring-shaped auxiliary wheel formed of a metallic material is inserted into and coupled to the outer circumferential surface of the main wheel formed of a plastic material, thereby increasing a rotation speed of the wheel due to a local mass increase, which is caused by the insertion of the metallic material into the wheel, at the same volume by using the difference in specific gravity (density).

According to the present invention, such a configuration facilitates the variation of mass compared to a conventional structure formed of a single material through the difference in specific gravity (density) between the main wheel and the auxiliary wheel, thereby further improving driving performance.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of the configuration of a conventional wheel for skates;

FIG. 2 is a cross-sectional view of a wheel having a heterogeneous material disposed therein according to an embodiment of the present invention;

FIG. 3 a cross-sectional perspective view of the wheel having a heterogeneous material disposed therein according to the embodiment of the present invention;

FIG. 4 is a cross-sectional view of a wheel having a heterogeneous material disposed therein according to another embodiment of the present invention; and

FIG. 5 is a cross-sectional perspective view of the wheel having a heterogeneous material disposed therein according to the embodiment of the present invention.

<Description of the Reference Numerals in the Drawings>  10: Hub section  11: Inner ring portion  12: Outer rim portion  13: Spoke  20: Tire  31: Bearing  32: Spacer member  33: Fastening bolt  34: Nut 101: Tire 110: Main wheel 111: Core part 112: Protruded recess 120: Auxiliary wheel

BEST MODE

Hereinbelow, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings in order to allow an ordinary skilled person in the art to easily implement the invention. In the following description, it is to be noted that, when the functions of conventional elements and the detailed description of elements related with the present invention may make the gist of the present invention unclear, a detailed description of those elements will be omitted. Further, the same reference numerals refer to similar elements throughout the drawings.

In addition, the expression ‘the connection of a first element with a second element’ may include embodiments in which the first and second elements are formed in direct contact, and may also include embodiments in which additional element may be formed between the first and second elements, such that the first and second elements may be connected indirectly. It will be further understood that the terms “comprises” and/or “comprising”, or “includes” and/or “including”, when used in this specification, specify the presence of stated features, but do not preclude the presence or addition of one or more other features.

FIG. 2 is a cross-sectional view of a wheel having a heterogeneous material disposed therein according to an embodiment of the present invention, and FIG. 3 a cross-sectional perspective view of the wheel having a heterogeneous material disposed therein according to the embodiment of the present invention. As shown in FIGS. 2 and 3, a wheel having a heterogeneous material disposed therein may include a main wheel 110 and an auxiliary wheel 120 according to an embodiment of the present invention.

The main wheel 110 includes a stepped core part 111 and a urethane tire 101 that is an outer circumferential part thereof. The main wheel 110 is formed of a plastic material, which is different from a metallic material of the auxiliary wheel 20 to be described later. As shown in FIGS. 2 and 3, the main wheel 110 may be provided with a protruded ring-type recess 112, in which the auxiliary wheel 120, which is also ring-shaped, is inserted and coupled along a circumferentially central portion of the outer surface of the recess. Alternatively, as shown in FIGS. 4 and 5, the ring-shaped auxiliary wheel 120 may be embedded in the protruded ring-type recess 112 along the circumferentially central portion of the outer surface of the recess. In addition, as shown in FIG. 1, two bearings 31 and a cylindrical spacer member 32 are inserted into the core part 111 of the main wheel 110, and a fastening bolt 33 is inserted through the bearings and spacer member and is fastened with a nut 34, thereby forming an assembly.

The auxiliary wheel 120 is a ring-shaped member that is provided along a circumferentially-central portion of the outer surface of the main body 110, on which the tire 101 is provided. The auxiliary wheel 120 may be formed of a metallic material that is different from the plastic material of the main wheel 110. That is, the auxiliary wheel 120 may be formed of any one metallic material selected from the group including steel, aluminum, tungsten, brass, titanium, and stainless steel. In addition, as shown in FIGS. 2 and 3, the auxiliary wheel 120 may be inserted into and coupled to the protruded ring-type recess 112 on the outer surface of the main wheel in such a manner that it protrudes farther than the protruded recess. Further, as shown in FIGS. 4 and 5, the auxiliary wheel 120 may be embedded in the protruded recess 112 along the circumferentially central portion of the outer surface of the recess.

According to the present invention, the wheel is configured such that the auxiliary wheel 120 and the main wheel 110 have a difference in specific gravity (density), and the metallic auxiliary wheel 120 is fixedly inserted into, or otherwise integrally embedded in the protruded recess on the outer surface of the main wheel 110, thereby increasing a rotation speed of the wheel due to a local mass increase at the same volume, which is caused by the insertion of the metallic material into the wheel. Such a configuration facilitates the variation of mass compared to a conventional structure formed of a single material through the difference in specific gravity (density) between the main wheel and the auxiliary wheel, thereby further improving driving performance. That is, since a metallic material has higher specific gravity than a urethane material, when the metallic auxiliary wheel is coupled to the urethane wheel, an increase in local mass occurs at the same volume, thereby increasing a rotation speed of the resultant wheel.

The wheel in which the auxiliary wheel formed of a heterogeneous material is disposed in the main wheel 110 can be used for extreme sports, inline-skating, skateboarding, essboarding, kickboarding, or the like.

FIG. 4 is a cross-sectional view of a wheel having a heterogeneous material disposed therein according to another embodiment of the present invention, and FIG. 5 is a cross-sectional perspective view of the wheel having a heterogeneous material disposed therein according to the embodiment of the present invention. The wheel shown in FIGS. 4 and 5 has the same configuration as that of the wheel shown in FIGS. 2 and 3, except for a position where the auxiliary wheel 120 is provided. That is, in FIGS. 4 and 5, the ring-shaped auxiliary wheel 120 is integrally embedded in the protruded ring-type recess 112 along the circumferentially-central portion of the outer surface of the recess. That is, unlike the embodiment of FIGS. 2 and 3 in which the auxiliary wheel 120 is inserted into and coupled to the protruded ring-type recess that is provided on the circumferentially-central portion of the outer surface of the main wheel 110, in the present embodiment of FIGS. 4 and 5, the auxiliary wheel 120 is embedded in the circumferentially-central portion of the outer surface of the main wheel 110 by means of a die casting method. Here, in the case of insert-type coupling, the configuration may be such that, after the main wheel 110 is separated in a symmetrical manner, the auxiliary wheel 120 is arranged, and then the separated main wheel 110 is coupled and assembled thereto.

The present invention disclosed herein may be diversely modified and applied by an ordinary person skilled in the art to which the present invention pertains, and the scope of technical spirit of the invention should be defined by the accompanying claims. 

1. A wheel comprising: a main wheel (110) having a stepped core part (111) and a tire (101) formed of a urethane material as an outer surface thereof; and an auxiliary wheel (120) having a ring shape and provided on a circumferentially-central portion of the outer surface of the main wheel (110), on which the tire (101) is provided, in an insertion manner, wherein the main wheel (110) is formed of a plastic material, and the auxiliary wheel (120) is formed of a metallic material that is different from the material of the main wheel (110).
 2. The wheel of claim 1, wherein the auxiliary wheel (120) and the main wheel (110) have a difference in specific gravity (density) and the metallic auxiliary wheel (120) is coupled to the outer surface of the main wheel (110) so as to increase a rotation speed of the wheel due to a local mass increase at the same volume.
 3. The wheel of claim 1, wherein the main wheel (110) is provided with a protruded ring-type recess (112) in which the auxiliary wheel (120) is inserted into and coupled to along a circumferentially-central portion of an outer surface of the recess, wherein the auxiliary wheel (120) protrudes farther than the protruded ring-type recess (112).
 4. The wheel of claim 1, wherein the main wheel (110) is configured such that the auxiliary wheel (120) is integrally embedded in the circumferentially-central portion of the outer surface of the main wheel (110).
 5. The wheel of claim 1, wherein the auxiliary wheel (120) having the ring shape is formed of any one material selected from the group including steel, aluminum, tungsten, brass, titanium, and stainless steel.
 6. The wheel of claim 5, wherein the wheel in which the auxiliary wheel (120) is disposed in the main wheel (110) is used for extreme sports, inline-skating, skateboarding, essboarding, kickboarding, or the like. 